Expert systems for self-tuning control

The application of self-tuning control can in certain process control problems lead to improvements in economic, safety and control performance. However, the components of a self-tuning controller are more complex than conventional loop controllers and require considerable knowledge of a variety of advanced algorithmic techniques. In addition, as much detailed process specific knowledge as possible must be built into the self-tuner in order to select good design parameters for a given application. We identify a two-way knowledge threshold which must be crossed before self tuning control can be used and fully exploited on industrial processes. This chapter examines the components of the knowledge threshold present for self tuning controllers and considers some possible solutions. The use of expert systems to lower the knowledge threshold is discussed with reference to a prototype system.